A unique identifier : UUID GUID « Development Class « Java

A unique identifier

 * This file is part of the Echo Web Application Framework (hereinafter "Echo").
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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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 * A unique identifier.
public class Uid {

    private static final String machineIdString = Integer.toHexString(new Object().hashCode());
    private static int globalCount = 0;
    private final int count = ++globalCount;
    private final long time = System.currentTimeMillis();
     * Generates a new identifier String.
    public static final String generateUidString() {
        String idString = new Uid().toString();
        return idString;

     * Generates a new identifier.
    private Uid() {
     * @see java.lang.Object#toString()
    public String toString() {
        String timeString = Long.toHexString(time);
        String countString = Integer.toHexString(count);
        return machineIdString + "_" + timeString + "_" + countString;


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